Compound rotary steam-engine.



O. O. NYGAARD.

COMPOUND ROTARY STEAM ENGINE.

APPLICATION FILED AUG. 3, 1909.

952,465. Patented MarQ22, 1910.

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Amiga QsumQX QMR. W5 M 414% /wzzm 0. 0. NYGAARD. COMPOUND ROTARY STEAM ENGINE.

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0.0.NYGAARD. COMPOUND ROTARY STEAM ENGINE.

APPLIOATION FILED AUG. 3, 1909.

Patented Mar. 22, 1910.

8 SHEETS-SHEET 3.

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*0. 0. NYGAARD.

COMPOUND ROTARY STEAM ENGINE.

APPLICATION FILED AUG. 3, 1909.

Patented Mar. 22, 1910.

8 SHEETS-SHEET 4.

x a. :v |-I.,. k h V 3% .u i a 0. 0. NYGAARD.

COMPOUND ROTARY STEAM ENGINE.

APPLICATION FILED AUG. 3, 1909.

Patented Mar. 22, 1910.

8 SHEETSSHEET 5.

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0. 0. NYGAARD. comronma ROTARY STEAM ENGINE.

APPLIOATION'FILBD AUG.3, 1909.

Patented Mar. 22, 1910.

0. 0. NYGAARD.

COMPOUND ROTARY STEAM ENGINE.

APPLICATION TILED AUG. 3, 1909. 952,465. Patented Mar. 22, 1910.

8 SHEETS-SHEET '7.

(9707: W MW O. O. NYGAARD.

COMPOUND ROTARY STEAM ENGINE.

APPLICATION FILED AUG. 3, 1909. 952,465.

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CQMPQUNJD RQTARY STEAM-ENGINE.

Application fi led August '3,

To all moi-tom it may concern: I Be it known that l, OsoAn O. NYcAARm'a citizen of the United States, residing at the city of Newport, in the county of Providence and State of Rhode island, have invented certain new and useful Improvements in Compound Rotary Steam-.Engines, of

which the following is a specification.

My invention relates to rotary engines of the class in which steam 1s used as a motlve force against the revolving piston or rotor;

and it consists of a compound engine, the structural parts of one engine being substantially the same as the other engine, one structure acting as a high pressure engine and the other structure acting as a low pressure engine, and thel at-ter driven by the exhaust of the former, automatic means to cut off the main steam pressure during an approximate half revolution of the engine, and means to permit the engine to run in either direction.

The objects of my invention are to provide an improved engine which is equally steambalanced, so that it has equal power, the full revolution, will start with equal power at all points, which shall he eiiicient and reliable in operation, and economical in the use of steam.

With these objects in view, and such others as pertain to my invention, it consists in certain novel features ofconstruct-ion, arrangement, and combination of parts, as

hereinafter described and claimed.

In the accompanying drawings, Figure 1 represents a plan View of my improved rotary engine as compounded and constructed in accordance with my invention. Fig. 2 is an'end view of the high pressure engine, showing the main steam pipe connections thereforgand the gearing arrangement for actuating the main steam cut off mechanism. Fig. 3 is a face view of the "main piston or rotor of the high pressure engine, showing its steam abutments provided with springpressed packing-blades, and also arrangement of springs "to force against packingrings, the latter being removed. Fig. 4 is a detail section taken on line 4.4. of Fig. 2, showing the gears for actuating-the rockervalves of the steam cut oil mechanism. Fig.

' 5 is a transverse sectional view of the high pressure engine, taken on line 5.-5. of Flg. 1, showing one pair of oppositely disposed rocker-valves of thesteam cut ofi mechanism, after steam has been admitted tothe Specification of Letters Patent, Pafi mttec'l Mar; 22, 1193141).

1909. "Serial No. 511,054.

pressed packing-blades of the latter to cutoff the main steam pressure between the rotor steam-abutments, shown at half stroke or vertical mid-position in the engine-cylinder. Fig. 6 is a similar view taken on line 6,-6. of Fig. 1, showing the relative position of another pair of oppositely disposed rocker-valves, after steam has exhausted from the front of the jumper-pistons. Fig. 7 is a face view of one of the packing-rings for the rotor of the high pressure engine. Fig. 8 is a section of the ring takenfon line 8. '8. of Fig. 7. Fig. 9 is a detail sectional view of one steam" out ofi mechanism taken on line 9.- 9. of Fig. 5, showing one pair of rocker-valves, and steam inlet and exhaust pipe connections, and jumper-piston. Fig. 10 is a sectional view taken on line 5.5. of .Fig. 1, showing the relative position of parts, after steam has been admitted to the rear of the jumper-pistons and the blades 01 the latter carried free from the path of the rotor steam-abutments, which are shown in horizontal position or deadcenter line of .the engine. 11 is a similar view taken on line 6..6. of Fig. 1, show-. ing the relative position of parts, after steam has exhausted from the rear of the jumper-pistons. Fig. 12 is a lan sectional view taken on line 12-12. of ig. 10, showing the arrangement of spring-pressed pacln ing-blades'for the rotor and umper-pistons, and also means to guide the said packingblades evenly in their reciprocating movement. F i 13 is a detail sectional view taken on line 13-13. of F 12. ig. 14 is an end elevation of the low pressure engine, showing the gearing arrangement tor actuatin ism, an the small steam pipe and exhaust pipe connections therefor. Fig. 15 is a plan the main steam cut 0d mechanfront of jumper-pistons, to cause springof their adjacent steam slide -'valves, and

hand-operating means to move said slidevalves. Fig. 17 i is a side sectional view taken on line 26.26. of Fi 15, showing the other extreme position of t e slide-valves.

Fig. 18 is a planview of .one of the rotor steam-abutments, showing arrangement of s to force against the packing-blade,

' t e latter being removed. Fig. 19 is a sectional view taken on line 19.19. of Fig. 18. Fig. 20 is a transverse section of the steamabutment taken on line 20.20. of Fi 18. Fig. 21 is a plan view of the packinglade for the steam-abutment. Fig. 22 is a crosssection of the blade, as seen on line 22.22. of Fig. 21. Fig. 23 is an end sectional view taken on line 27.27. of Fig. 1, showmg the hand-lever and its connections forreversing the movement of the compound en ine. The direction in which the sectional gures are viewed is indicated by arrows at thelines specified.

Like reference characters indicate like parts throughout the views.

a For the purpose of attaining the highest economy in the use of steam to drive my improved engine I compound the engine as shown, one engine acting as the high pressure engine, as A in Fig. 1, and the other e ngine, whose cylinder is somewhat larger 1n size than the cylinder of former englne, acting as a low pressure engine, as A and adapted to be driven by the exhaust ofsaid high pressure engine, and steam is admitted into each cylinder twice per revolutlon, so that the speed, and steam pressure are the same in both engines and the volume of steam used and the ower developed by the en 'nes are substantlally the same.

eferring to Figs. 1 and 15, for the purpose of attaining brevity in the descr pt on, a designates the engine-shaft; b the engmec linder concentric to said shaft; 0 the rotor;

, d the cases for inclosing the main rotary steam-valves; e, e the chests for inclosing the steam slide-valves; f, g the case an cylinder respectively for inclosing the jumper-piston and rocker-valves of the steam cut off mechanism, and h the hand-lever for reversing the rotative movement of the.

engine.

In construction the cylinder 6' is madein one casting, having 21. depending support a that terminates with a base a as shown in Fi 5, and a head a is located at the rear en of said .cylinder and projects beyond the outer peripheral surface of the latter, and from at a point within the cylinder said head a extends inwardly and longitudinally in the form of an annular flange a. which terminates with a wall a arranged transversely of the cylinder and havlng a hub a bored to receive a acking and land a, to act as a stuflingox surroun ing the engine-shaft, in the manner shown in Fig.- 15. The head a is provided with four ports a a and a a. communicating within the cylinder 6 and near the shell thereof, and each pair of ports a and a. are located diametrically o posit'e each other and near to the horizonta axial center of the cylinder, as shown in Fig. 5, and either pair of these diametrically opposite port's become steam inlets and exhausts in reversing the motion of the engine. At each side of the cylinder 6 projects a flange-head, as at points a, a, and each flange-head is provided with a narrow slotted opening a extending the full length of the cylinder, and on the line of horizontal axial center thereof, to receive a slidin movement therethrough of the packing-% ade structure of the jumper-pistons, presently described. 1

The front end of the cylinder b is closed by a bonnet a which is secured in place by bolts a, and said bonnet is the same size in diameter as the head a of said cylinder and the same contour as said head, having an inwardly and longitudinally extending flange a to register with the cones onding annular flange a of said head an a wall a which terminates with a hub a that is bored to receive a packing and gland a,

to act as a stufling-box surrounding the engine-shaft.

The rotor 0 is a cylindrical casting, having a central hub c keyed to the engineshaft and of a length to fit between the wall a of the cylinder-head a and wall a. of the c linder-bonnet a, and centrally of said hub is a web a that terminates with a deep annular wall 0 which rests upon the surfaces of the annular flanges o'f sald cylinder-head and its bonnet. The annular wall 0 of the rotor is of a length to extend near to the wall a of the cylinder-head and wall a of the bonnet, and of a depth to be clear of the ports a and a. e

The rotor is provided with two diametrically opposite steam abutments, the struc'tural parts of which are shown by Figs. 18 to 22 mclusive, and in which a is the steam wallabutment of a length to extend between the cylinder-head and its bonnet, said abutment having a led e c to snugly fit within a dovetail groove ormed in the annular wall 0 of the rotor and extending longitudinally of the latter, as at a point 0 in Fi 10, and said abutment c is provided with a channel c to receive upwardly curved springs 0 0 which are secured to said abutment by screws 0 0 This wall-abutment has a series of integral ribs 0 0 projecting from its sides and having their edges inclined from at a point on the outer surface of the annular wall 0 of the rotor and inwardly to the shell of the engine-cylinder, forthe pur ose of giving stability in holding the .wal -'abutment rigid against the steam pressure; A packing-blade c rests upon the top faces of the wall-abutment 0 and of the same length as the latter and said blade has a ledge 0 to rest upon the springs 0 so that the latter cause'said blade to bear n frictional contact upon the engine-cylmder.

Each face of the annular wall 0 of the rotor c is provided with a channel, as at points 0 0 in F 1g. 15, to receive therein upwardly curved springs 0 ,0 which are secured to said wall by screws 0, 0 as shown in Fig. 3. Packing-rings 0 0" have each a concentric ledge c 'to rest upon rotary-valve al having a short central hub.

in which is made fast a horizontal shaft d whose axial center is in alinement with and at right angles to the engine-shaft a Each rotary-valve d disposes two opposite se mental flanges d d in order. to prom e therebetween main steam ports d 03 as shown. in Fig. 16, and said flanges d extend the full len th within each case (i and are integralwit short webs d, d of the hub of each rotary-valve, as shown in Fig. 24. "Each case d has a verticalhead d which is bolted to the chests (2,6 containing the slide valves, and each head d is provided with two ports d, 03 extending long1- tudinally of the latter and communicating with the interior of each case d, and, as seen in Fig. 16, each port d extends radially from the center of the valve-shaft d and communicates with the interior of either valve-chest a. Each valve-shaft d has a miter gear i fast thereon and each gear meshes with a miter ear d fast on the engine-shaft,.and thus t e rotary-valves are caused to rotate at uniform s' eed. Each case d is provided witha stu surrounding each valve-shaft d Referring to Fig. 1, s is the main steam pipe, which extends centrally and longitudinally of the engine and unites with transverse branch connections 8 ,8 whose the engine.

Referring to Fi 16, each steam-chest e is bolted to the cy inder-head a each chest having a rectangular opening therethrough for the vertical movement of each slidevalve 6 which is substantially C-shaped in normal vertical position, the vertical portion of said slide-valve e bearing against the head d of the valve-case d and of a height to cover port d, while the lateral extensions of said slide-valve e are distanced apart to permit the steam pressure to pass from the open port of the valve-case '01, through the space left between the valvechest 6 and slide-valve e through one port 0. of the engine-cylinder and against one of the wall-abutments c of the rotor 0, while i the exhaust from the latter passes throughthe other port a of the en inc-cylinder, through the slide-valve e, an out through either exhaust-pipe e, one end of which communicates within either chests; and its other end'communicating with the interior of either rotary valve-case d of the low pressure engine'A in the manner shown in Figs. 15 and 16.

The construction of the steam cut ofi mechanism, of which two alike structures are employed on each engine, is as follows:

On each flan e-head a of the engine-cylinder is secure a plate e of the same size as the'fiange of said head, and said plate is provided with a central opening e, for the movement therethrough of the rod of the jumper-piston, in the manner shown in Figs. 5 and 12. f designates the case for inclosing the reciprocating jumperpiston 1 whose axial center is at a right angle to the axial center of the engine-shaft a, and said case has a flange-head, as at f in Fig. 9, and

through which head bolts pass for securing said case to the plate 6 The jumper-piston f fits the bore of the case and is provided with the usual packing-rings, as at f in Fig. 5, and the rod i has one end centrally secured through said piston and its other end centrally secured to a cross-bar f slidable in the slotted opening a of the flangehead a, said bar being of a length to extend betweenthe cylinder-head a and its bonnet-head a and said bar provided with a channel f extending longitudinally therethrough, as shown in Fig. 12. A packingblade f fits the slotted opening a, said blade being the same length as the bar 7 and having a ledge f to fit within the channel f and rest upon upwardly curved springs 7, f which are secured to said bar by screws f", f". To prevent displacement of the blade 1 on the bar f said blade has each end of its ledge f projecting rearward to form lateral extensions f f which are each provided with short elongated openings f, f to receive therethrough pins f",

f whoseends are secured in the sides of said bar f*, as shown in Figs. 12 and 18, thus when the blade f is forced in contact with the peripheral surface of the rotor 0 a yielding movement of the said blade structure is had to overcome the shock against said rotor and at the same time prevent the piston f from striking against the inner head of its case J. In order that the crossfee bar ff may move evenly throughout its forward and backward movements I provide two lifting-guides at each end of the cylinder-plate e and in which 9 is a disk which is bolted to said plate and having two oppositely disposed arms 9 9 whose out'er ends 'are bifurcated for connection with links g g and centrally of the disk 9 in a stem 9 whose outer end is also bifurcated for connection with similar links 9*, g, and the latter having their inner ends connected to the inner ends of saidlinksg and the inner end of the stem 9 is made fast to said bar f, thus when steam forces the piston f to carry its blade in contact with the rotor the links are brought to the dotted position shown in Fig. 12, and when steam is admitted to cause a reverse movement of the piston the said links will be brought to their full line position shown in said figure and the bar caused to come evenly in contact with the plate 6 and the piston prevented from striking against the outer head g of its case. A suitable packing is mounted in the case f and surrounds the piston-rod f, as at g in Fig. 5. Referring to Figs. 5 and 9, the pistoncase 7' has an integral fiat top portion, as at f", of a size to receive thereon an integral base 9 of the cylinder 9, and which top portion and base are secured together by bolts in the manner shown in said figures. The cylinder g has its axis at a right angle to the axis of the case f and longitudinally of the engine-cylinder, and said cylinder 9 is divided by a transverse partition 9" which is provided with a small centrall circular opening of a size to receive theret rough the valve-stem g, as at a point g. The portions of the valve-stem 9 within the bores of the cylinder 9 are flattened, as at points 9 and on these flattened portions two rocker-valves g, 9 are mounted and kept from displacement by means of screwthreaded heads 9 and g" that engage in-' terior threaded portions formed at each end of said cylinderg, the latter head being provided with a suitable stufiing-box, as g, to surround said stem as shown. In the side walls of the cylinder 9 are formed two narrow steam-ducts g and g communicating with the rocker-valves g, g respectively, and which ducts extend from at a point near to and below the valve-axis of said cylinder, and each duct registering with a similar size duct formed throu h the case I and communicating with its piston-bore at eachend thereof. The rocker-valve g has a long se mental bearing-surface g of a length su cient to close one of the steamducts of its cylinder 9 and leave open the opposite duct, in'themanner shown in Fi 5, and also a narrow upper wall gr exten ing longitudinally of said valve and arranged to permit live steam to enter from a small steam-pipe g and pass through steam-passages left by the cutaway portions between said wall and said bearing-surface, as at points g ,.g and enter through either duct 9 g",'according to the swing-movement of said valve. The rocker-valve g has a long segmental bearing-surface, as at a point 9 at the right of Fig. 6, of a length suflicient to close one of the steambonnet a", said ducts of its cylinder 9 and leave open the opposite duct, in order that the cutaway portion between the ends of said bearing surface may act as a'steam-passage g to receive the exhaust-steam from the pistoncase f and pass from either duct 9", "g out through a small exhaust-pipe g" whlch com-,

'municates with the mam exhaust-pipe e Each pair of valves g, 9 receives its oscillating motion by means of a lar e spur gear 9 keyed on the 'engine-sha a, as shown in Figs. 4 and 5, and which gear meshes with a small spur gear 9 loose u n a stud g made fast in the engine-cylin ergear 9 having a pin g 0 projecting be'yon its axial center for con nection with the ends of rods gt", 9, whose opposite ends are attached to upwardly extending arms 9 9 secured on the stems g g of each air of rocker-valves, in the 5 manner shown in Fig. 2. The small steampi e g, which leads from each rockerva ve-cylinder g, unites with an inverted T- shaped connection 9 having a short branch steam-pipeconnection g to the overhead main steam-pipe s, and in this branch-pipe g is mounted a throttle-valve 9' for regulating the flow of steam to operate the jumper-pistons. I

.Refe'rring to Fig.5, the type of rocker valve islocated at the points designated by re erence numerals 1, 1, 1, 1 in Fig. 1, while the type of rocker-valve g is located at the points 2, 2, 2, 2 in'said latter figure, thus whensteam is admitted to opermain steamways 2', i in the engine-cylinder.

Referring to Figs. 16 and 23, a shaft k 110.

has its ends loosely mounted in the .solid heads of each engine-cylinder b and I), as at points k h and on said shaft is centrally secured two alike levers k, 71. whose ends are bifurcated to connect with links h, h, which 11 have their opposite ends secured in the bi-. furcated portions of vertical rods h, h, and each rod made fast in the u per part of each slidevalve c. On the sha b is made fast one endof a laterally projecting lever'k the outer free portion'of which acts as a handle,

as at h, and on said lever is mounted a headed stud l located near its handle and passing through a slotted opening h formed in a post h having a base '71., which is bolted to the engine-bed h. The stud h has its free portion screw-threaded to receive thereon a thumb-screw it, which acts as a clamp to impinge against in holding said lever h firmly in place upon said post. The opening 139 sea-tee it in the" post is in the form of an arc whose radius is struck from the center of the shaft h and of a length to permit said lever to swing the slide-valves e to their extreme upward or downward positions, to cause the engine or compound-engine to run righthand or left-hand, as may be desired.

The upper part of each steam-chest e is provided with a stufling-box surrounding each rod k of each slide-valve e, as shown in Fig. 16.

Beyond the gears g g for actuating the rocker-valves, the engine-shaft a is mounted on the journal-bearings of pillow-blocks j, j,

and the base of each block bolted to the engine-bed-plate h, as shown in Fig. 16.

In this construction of compound engine its co-axial shafts a, a have each a hub is made fast thereon and each hub has an integral annular flange, as k lcfi which are secured together by bolts Z, Z, in the manner. shown more clearly in Fig. 15. The bevel gears d d", d are each of equal size, and each pair of valves 1, cl for one engine is positioned at a quarter turn of the pair of valves d, al for the other engine, thus as one pair of said valves is taking steam the other pairis closed against steam. Each pair of valves d d is driven in opposite directions by means of the driving miter gear 41., and each pair of said valves rotates at the same speed as the rotor 0. Each rotor c has its steam ab'utments 0", c positioned .a

quarter way around from the rotor-abutments of the other engine.- Each set of spur gears g g, for actuating the steam cut ofi' mechanism, is in ratio of two to one.

Having now described the structural parts of my improved engine I will proceed to explain its 0 eration.

The sma l throttle-valve 9 is first opened to permit steam from the small pipe (p to enter through theouter passage 9 an passage 9, provided respectively by the right and left hand rocker-valves shownin Fig. 5, through the outer ducts g, g and force the jumper-piston-blades f, f in contact with the peripheral surface of the rotor o of high pressure en ine A, and in the same manner cause the piston-blades of'the low pressure engine A to move free ofits steamwaysz', 2', as shown in Fig. 5. s The main throttle-valve d is next opened to start the compound engine, which, we Wlll assume, rotates in the direction indicated by the arrows on the engine-shafts a, a, and the pair of slide-valves fie, 6 at the right side of the engine, held at their lowermost position, as shown in Fig. 16, while the opposite air of slide-valves e, a, at the left side of the engine, isheld at their uppermost position, as shown in Fig. 17. v

Referring to Fig. 16, the live steam passes through one of the rotary-valve-ports d at' .the right side of the high'pressure engine,

through the upper on d in the cylinder of said valve, th'encet rough the space left by shown in Fig. 5, and while the above steam action takes place the live steam operates in the samexmanner from the opposite rotaryvalve of said high pressure engine, except that it passes from last mentioned valve through the lower port d" of the valve-cylinder, thence through the space between the lower slide-valve e and its chest, thence through the lower left hand port a of the engine-cylinder b, and against the bottom centrally positioned steam abutment a", as shown in said latter figure. Still referring to Fig. 5, as the rotor 0 turns toward the left it expels the exhaust from the steamways z, a, in the direction indicated by the arrows m, m, through the diametrically opposite enginecylin er-ports a a, thence into and through each slide-valve e a and out through the main exhaust-pipes e e In the position of parts shown in Fig. 5, before the jumperpistons reach their inner position as shown they expel the exhaust steam, from the pipes g 9 out through the inner ducts g, g, and the next adjacent pair of rockervalves g, 9 (Fig. 6) assume a position to permit said exhaust to pass out through the small pipe connections g, 9 that communioate with the main exhaust-pipes e 6 After the steam-abutments c 0 of the rotor c of this high pressure engine, has expelled the exhaust through the ports of the cylinder 5, the small spur gear 9 will have made a half revolution and thereby bring the rocker-valves 9 g to such position as to cause steam from the small pipes 9 to force against the inner faces of and carry the jumper-pistons to the position shown in Fig. 10, and as soon as said pistons reach this osition the steam-abutments 0 will then e at their horizontal axial center of this engine, as seen in said figure, and rior to this position of arts the exhaust in front of said pistons wil be expelled through the outer ducts'g", g" and the adjacent rockervalves g, g (Fig. 11) at such position to permit said exhaust to pass through the short pipes g, g to the main exhaustpipes e 6 As the live steam passes into the upper right-hand engine-cylinder-port a and out through the diametrically opposite lower left-hand port a to drive the rotor of the high pressure engine, as in Fig. 5, the exhaust from the cylinder 1) of said engine operates in the same manner through the alike ports, to drive the rotor of the low pressure engine, the worked steam finally passingout through pipes :11, a: secured in .the steamchests of the latter engine and communi- For a sin le engine the coupling, formedt a la g full st am pressure t force the-jam ,r-

pistons inwardly together and cause t eir blades to instantly cut oil the mam steam pressure from'the mainexhaust 1n the engine-cylinder, and when sa1d abutments reach said ports said valves act in the same manner to cause said blades to simultaneou l w thdraw from the main ways or the travel of-said abutments.

T c fin r-valves d, of the low pre r engine K are adapted to cut oil steam very early, in order to permit the steam-expansion to perform its work for the remaining part of revolution of the rotor of this engine.

by the huhes lo, k maybe dispensed with and the .ex anst-pipes e, e lead direct pipe for communicating wlth the atmosphere. 1

What I claim and desire to secure by Letters Patent,

1.- Ina rotary steam-en ne, the comb nation of a stationary c lin r provided wlth two port at ao 'si e th an engine shaft; a rotor fast on said shaft, concentric with and of lesser diameter than thee linder so as to rovide steamways from sai ports, and said rotor having two oppositely disposed and longitudinally arranged steamabutments ro each with a SPI1 Ilgressed pacliing-blade to bear against the bore of the cyhnder; two rotary-valves arranged to receive'the main steam pressure therethrough; a gearing arrangement driven by the sha t to rotate said valves at the same speed as the rotor; a slide-valve interposed between two ports'leading from each rotaryvalve and each said pair'of orts in the'cylinder; means to hold one s ide-valve at its one extreme of movement While the other slide-valve is held at its other extremeof movement in order that the steam may enter through the upper or lower oI't of a 'pair at one side of the c linder an a ainst one roltor-abutment WhllB the other s idesvalve per.- mits the steam to pass through the u per or lower port diametrically opposite 1t first mentioned port and against the other rotorabutment, and a jumper-piston mechanism mounted on each side of the cylinder, actuated by the engine-shaft and driven by steam to respectively cut oil? the main pressure simultaneously at points between each pair of the cylinderorts, and permit the main exhaust to pass gem the steamways through the remainin two diametrically opposite ports, into an. from the slide-valves.

2. In a rotary steam-engine, the combination of a cylinder having an integral head provided with two orts at each side of the cylinder, each port coated near to the hori-- 'zontal axis of the latter, and said" cylinder having integral-flange-heads rovided each with a narrow lon itudinal arranged slotted .o nin ;-a fix bonnet nclosin the open en of te cylinder; an engine-soft; a rotor fast on the shaft and concentric with the cylinder, of lesser diameter than the latter in ,order to leave a steamway communicating With the ports; a s ring -pressed packing-ring mounted in eac face ofthe rotor to bear against the head of the cylinder and bonnet of the latter; two fixed steam-abutments mounted opposite each other on the rotor and longitudinally thereof; a spring-pressed packing-blade in each abutment to bear against the bore of the from eac rotary-valve; two jumper-pistons .havln each a rod-connection with a crossbar shdable in each opening of the flangeheads of the cylinder; a spring-pressed means to move each cross-bar evenly in each '90 packing-blade carriedby each cross-bar;'

opening of the flange-heads; means to automatically permit steam to force the pistonblades incontact with the peripheral surface of the rotor when the main pressure may then pass from one pair of diametrie ally opposite cylinder-ports and against the rotorrabutments while the other pair of diametrically opposite cylinder-ports discharges. through the slide-valves, and the piston-bladesthen brought'free of the steamways for another operation of the main steam pressure,

3. In a rotary steam-engine, the combination of a stationary cylinder rovided with a pair of orts, at each side 0' the cylinder, and through its head and centrally of and near to the horizontal axis of said cylinder, and the latter provided with oppositely arffln'ged slotted openings extending between each its axlal center on the axis of the cylinder; abonnet inclosing the open end of the cylinder; a circular rotor centrally mounted on the shaft and carrying two oppositely disposed steam -.abutments; a springsressed packing-ring mounted in each face of the rotor; a spring-pressed packing-blade mounted in each abutment of the rotor; jum er-pistons whose rods carry cross-bars to side in the slotted openings .of the cylinder; a spring-pressed packing-blade carried by each bar to contact with the peripheral surface of the rotor; means actuated by the shaft to permit the main steam pressure to enter through two of the diametrically o posite ports and against one side of-the a utments while the steam at the pair of ports; an engine-shaft having 4 permit a steam pressure to simultaneously withdraw the pistons so that their blades become free of contact with the rotor and path of its abutments.

4. In a rotary steam-e ine, the combination of a stationary cylin er provided with ports in its head and also having an integral flange-head provided with a slotted opening centrally of the ports; a bonnet to close the open end of the cylinder; an en inc-shaft; a rotor fast on said shaft an carrying oppositely disposed steamabut-merits; a spring-pressed-blade in each abutment; a

steam-chest secured to the cylinder; a steam case secured to the chest and provided with ports; a slide valve closing-one port of the cylinder and leaving open one port of the case; a valve-shaft; a rotary-valve'mount ed in the case and provided with ports to receive the main steam pressure; a bevel gear fast on the engine-shaft; a bevel gear fast on the valve-shaft and in mesh with the first mentioned gear; a plate made fast on the flange-head; a steam-piston-case mounted on the plate and provided with a pistonbore having a narrow port at each end thereof; a" jumper-piston having a rod-connection with a cross-bar slidable in the slotted openin a spring-pressed blade carried by the er; a small steam-cylinder mounted on the steam-case and having a transverse partition so as to provide two steam-chambers and each having oppositely arranged narrow ports communicating with the ports in said piston-case; a valve-stem through the chambers of the small cylinder; a steam-pipe communicating with one chamber; a rocker-valve fast on the stem and having a large bearing-surface to close one portin its rocking movement and also having a wall dividing two cutaway passages; for steam to enter one or the other, according to the rockin movement of said valve;

anexhaust-pipe roin the other chamber; a

did

second rocker-valve fast on the stem and having a large bearing-surfaceto close one port in its rockin movement and also a cutaway passage or the exhaust to clear from; a large spur-gear fast on the engineshaft; a stud fast in the cylinder honnet; a small spur gear loose on said stud and in mesh with first mentioned spur gear; a pin secured in and beyond the axial center of second mentioned spur ear; an arm having one end fast on the Va ve-stem; a rod-connection from the free end of said arm to the pin of small spur gear, and means to carry the cross-bar evenly in its movement from the engine-cylinder; v

5. In "a rotary steam-engine; the combination ofa stationary cylinder provided with two ports arranged diametrically opposite each other and an exhaust-port near each steam-port, and said cylinder having integral projecting flange-heads provided each with a long slotte opening centrally of each steam-port and exhaust-port; a driv ing-shaft; a circular rotor fast on said shaft, concentric with the cylinder and having op positely disposed steam-abutments; means to keep the end faces and abutments of the rotor. steam-tight; two steam-chests; a slide valve in each chest to admit the main steam pressure a ainst two diametrically opposite faces of t e abutments while the exhaust passes through each valve; two valve-cylinders provided each with two ports communicatin'g with each chest; a rotary-valve in each last mentioned cylinder and each rotary-valve driven by power to admit the main pressure through the steam-ports of the. first mentioned cylinder; jumper-pistons Whose rods have each a cross-bar slidable in the opening of each flange-head, and each bar provided with a packing-blade; rocker-valves; and means actuated by the driving-shaft to move last mentioned valves, to admit steam to the front and exhaust from the rear of each piston to respectively force each blade in contact with the periphera; surface of the rotor, at'such time when its abutments leave the steam-ports of first mentioned cylinder and withdraw the blades from .the path of said abutments when the latter reach the exhaust-ports of said first mentioned cylinder.

6. In a rotary steam-engine, the combination of a stationary cylinder provided with two steam-ports arranged diametrically opposite each other and an exhaust-port near each steam-port, and said cylinder having integral flange-heads provided each with a slotted' opening extending the length of the bore of the cylinder and centrally of each steam-port and each exhaust-port; an engine-shaft; acircular rotor fast on said shaft and carrying. oppositely disposed sprin pressed steam-abutments to contact wit the bore of said cylinder; steam-chests; rotary-valves arranged to deliver the main steam pressure through said chests; means actuated by the shaft to rotate said valves; jumoer pistons, each havin a rod-connection with a cross-barjwhich is provided with a springpressed packing-blade; a slidevalve in each chest, so positioned thatv the main steam pressure is admitted over one valve and against the face of one abutment while the pressure is admitted under the other valve and against the opposite face of the other abutment, and the exhaust out from within each valve; means to move each slide-valve simultaneously to cause the engine to run in either direction; a rockervalve to admit steam against each piston and cause the blade of the latter to contact with the peripheral surface of the rotor after its ahutments pass the steam-ports; a'

rocker-valve to cause steam to exhaust from each piston in the withdrawal of the blades from the path of the abutments, and means actuated by the shaft to operate said rockervalves. p a 7. In a rotary steam-engine, the combination of a stationary cylinder provided with four ports throu h its head, and in which two form inlets iametrically opposite each other, and the other twooutlets located near to said inlets, and said cylinder provided with a slotted opening centrally'of each inlet and outlet port; a driving-shaft; a circular rotor fast on said shaft and carrying two oppositely disposed steam-abutments which project through steamways continuous from the ports; a packing-blade carried by each abutment to contact with the bore of said cylinder; a packing-ring mounted in each face of the rotor to contact with the cylinder-head and its bon-v net; means to automatically admit the main seam pressure through the inlets and against one side of the abutments, and to exhaust from the other side of the latter, through the outlet-ports; jumper-pistons having each a rod-connection with a cross-bar slidable in the opening of each flange-head; a packing-blade carried by the bar; means actuated by the shaft to respectively permit iston-blade's in contact steam to force the with the 'periphera surface of the rotor,

v and withdraw said blades from the steaming'centrally of each steam-port and each exhaust-port; a bonnet inclosing the rotor; valve-cases, each communicating with a main steam-pipe, and each case provided with two inlets; steam-chests between the valve-cases and cylinder and each case communicating with an exhaust-pipe; a rotaryvalve in. each case and arranged to deliver the steam pressure throu h either inlet; means actuated by the sha to rotate each rotary-valve at the same speed; a slidevalve in each chest and communicating with each exhaust-pipe; means to carry the slidevalves to their extreme opposite positions in order that the steam may pass through the steam-ports and against the abutments, and jumper-pistons having each a rodconnection with a cross-bar slidable in the t 0 pass over the steam-ports and to release the 7 blades when the abutments reach the exhaust-ports'.

9. In a rotary steam-engine, the combination with the driving-shaft; a circular rotor concentrically mounted and made fast on the shaft, said rotor having a deep annular Wall provided with two oppositely arranged and longitudinally extending dovetail grooves formed in its peripheral surface and also provided witha circular channel formed in each face of said wall; steam-abutments, each having a ledge to fit in each groove of the rotor-wall, and each abutment provided with a longitudinally arranged channel; a series of springs secured in-the channelof each abutment and each spring having its free portions curving upwardly; a packing-blade having a narrow ledge to fit within the channel and rest u on the springs of each abutment; a secon series of springs secured in the channels of the rotor-wall and each spring having its free portions curving outwardly, and a circular packing-ring having a central ledge to fit within the channel and rest upon the springs of said rotor-wall.

10. In a rotary steam-engine, the combination with the driving-shaft carrying a rotor which"has steam-abutments mounted thereon, of a stationary cylinder having a flange-head provided with an openlng therethrough, and also a steam-port and an exhaust-port outwardly from said opening and in the path of the rotor-abutments; a valve-shaft; a rotary-valve fast on last said shaft and arranged to permit the main pres sure to enter against the steam-abutments; a bevel arfast on last said shaft; a second beve gear fast on the driving-shaft and in mesh with first said gear; a slide-valve between said rotary-valve and said cylinder and arranged to discharge the exhaust therefrom; a plate secured on the flangehead and provided with a small centrally 115 arranged opening; a small cylinder mounted on said late and provided with a duct at each end of its bore; a jumper-piston havin a rod-connection through the opening 0 said plate and carrying a cross-bar 120 slidable in the openingof the flange-head;

.a case mounted on the small cylinder and provided with two chambers each communicating with oppositely arranged ducts that lead to the ducts in said small cylinder; a steam-pipe to one chamber; an exhaustpipe to the other chamber; a valve-stem;

,a rocker-valve fast on said stem and having a bearing-surface to cover one duct 1n sald case and provided with two steam-passages to deliver the pressure through one or the other of said ducts; a second rocker-valve fast on said stem and having a large bearing-surface to cover one duct in the other chamber of said case and provided with one steam-passage for the exhaust to pass from, and a gearing arrangement to operate said rocker-valves.

11. In a steam-engine, 'the combination with two co-axially arranged driving-shafts coupled together, a rotor fast on each shaft and each rotor having a pair of oppositely disposed steam-abutments, and one pair being located a quarter way around from the other pair, a stationary cylinder concentric of each rotor, one cylinder acting as a highpressure and the other acting as a low-pressure, each cylinder provided with two inlets arranged diametrically opposite each other to receive the main pressure therethrough and an outlet for the exhaust near each inlet, and-each cylinder having a pair of oppositely-projecting flange-heads rovided each with a slotted opening exten ing centrally of each inlet and exhaust; a pair of steamchests on each cylinder and communicating with the inlets and exhausts of the latter; a pair of valve-cylinders on the chests and each valve-cylinder provided with two ports communicating wit the latter; exhaustpipes leading fromthe chests of the highpressure cylinder to the valve-cylinders of the low-pressure cylinder; a' rotary-valve in each valve-cylinder, each rotary-valve for one main-cylinder provided with two ports located a duarter way around from the two ports in he pair of rotary-valves for the other main-cylinder; a slide-valve in each chest to communicate with either inlet or exhaust of the main-cylinders; means to carry one pair of slide-valves at one side of the engine to a position opposite of the pair at'the other side to reverse the movement of the engine; a plate mounted on the flangeheads of each main-cylinder; a jumper-piston having a rod-connection with a crossbar slidable in the opening of each flangehead; a packing-blade carried by each bar; and means to automatically force by steam pressure the blades of one pair of pistons in contact with a rotor while the blades of the next pair of pistons withdraw from the path of the ste'am-abutments of the other rotor, and means to .cause each cross-bar to slide evenly in its reciprocating movement, substantially as shown and described.

In testimony whereof I aflix my signature in presence of two witnesses.

' OSCAR O. NYGAARD.

Witnesses:

O. T. HANNIGAN, JAMES M. GILLRAIN. 

